Pd-Au/CNT催化剂的甲醇电氧化性能研究

Study on performance of Pd-Au/CNT catalyst for methanol electrooxidation

采用乙二醇还原法制备了碳纳米管负载Pd-Au双金属催化剂,并用于碱性介质中甲醇的电化学氧化。考察了Pd与Au摩尔比对燃料电池催化性能的影响。结果表明,Au的引入在一定程度上改善了Pd纳米粒子的分散性能,增大了催化剂的电化学表面积。当Pd与Au的摩尔比为1∶0.2时,Pd-Au/CNT催化剂具有最高的甲醇氧化活性,其甲醇氧化峰电流密度约为Pd/CNT电流密度的1.34倍。经过1200 s的单电势阶跃计时电流试验,Pd-Au/CNT(1∶0.2)催化剂的活性衰减率仅为42.3%,显著低于Pd/CNT催化剂,显示出良好的抗中毒能力。

Carbon nanotube supported Pd-Au bimetallic catalyst is prepared by means of ethylene glycol reduction method and used for the electrochemical oxidation of methanol in alkaline medium.The influence of the molar ratio of Pd to Au on the catalytic performance of fuel cells is investigated.The results show that the addition of Au improves the dispersion performance of Pd nanoparticles and increases the electrochemical surface area of the catalyst to a certain extent.As the molar ratio of Pd to Au is 1∶0.2,Pd-Au/CNT catalyst has the highest methanol oxidation activity and the peak current density of methanol oxidation is about 1.34 times that of Pd/CNT.The activity decay rate of Pd-Au/CNT(1∶0.2)catalyst after 1,200 s single potential step timing current test is only 42.3%,which is significantly lower than that of Pd/CNT catalyst,showing good anti-poisoning ability.